Ice drilling teams. Above: a team under Lonnie Thompson carrying equipment up Huascaran, Peru,
the world's highest tropical mountain. Bringing ice cores back to civilization, still frozen, was a tremendous challenge. Below: extracting a 6-meter core
segment from the drilling apparatus in subzero temperatures at the GISP2
site in Greenland.

Photos National Oceanic and Atmospheric Administration
Paleoclimatology Program/Department of Commerce, from NOAA
site. Upper by Lonnie Thompson, Byrd Polar Research Center, The Ohio
State University. Lower by Kendrick Taylor DRI, University of Nevada-Reno.